Astaxanthin

Fig. 3. Commeicially important carotenoids P-caiotene (10), canthaxanthin [514-78-3] (11), astaxanthin [472-61-7] (12), P-apo-8 -caiotenal [1107-26-2] (13), P-apo-8 -caiotenoic acid ethyl ester [1109-11-1] (14), and citranaxanthin [3604-90-8] (15).

Astacin (P,P-carotene-3,3, 4,4 -tetraone) [514-76-1] M 592.8, m 228", 240-243"(evacuated tube), 550,000 at 498mm (pyridine). Probable impurity is astaxanthin. Purified by chromatography on alumina/fibrous clay (1 4) or sucrose, or by partition between pet ether and MeOH (alkaline). Crystd from pyridine/water. Stored in the dark under N2 at -20°. [Davis and Weedon J Chem Soc 182 I 960.]... 

The molecular structure of astaxanthin. p-carotene is the same molecule where the =0 and —OH groups are replaced with hydrogens. 

An excellent case in point is the coloration of the American lobster, Homarus americanus. The pigment associated with the typical greenish-brown outer layer of the lobster shell is the carotenoid, astaxanthin (Figure A), an oxygenated derivative of p-carotene, also known as the molecule that imparts the orange color to carrots. 

Absorption spectra of astaxanthin (red line) in methanol and astaxanthin bound in crustacyanin protein (blue line). 

Arrhenius, Svante, 86,353 Arsenic, 573-574 Asparagine, 622t Aspartic acid, 622t Aspirin. See Acetylsalicylic acid Astaxanthin, 157 Asymmetric synthesis, 601 Atherosclerosis, 604... 

The results of this study may be helpful to understand the light-dependent photosynthetic activity of H. pluvialis. At the same time, the information presented here can be used for enhancing the volumetric biomass productivity of the astaxanthin-accumulating alga. 

This work demonstrated that an airlift system was suitable for the cultivation of Haematococcus pluvialis, one of the most effective microorganisms that could produce high potential antioxidant carotenoid, astaxanthin. Aeration was shown to be crucial for a proper growth of the alga in the airlift bioreactor, but it must be maintained at low level, and the most appropriate superficial velocity was found to be at the lower limit of the pump, i.e. 0.4 cm s". ... 

KAJIWARA S, KAKIZONO T, SAITO T, KONDO K, OHTANI T, NISHIO N, NAGAI S and MISAWA N (1995) Isolation and functional identification of a novel cDNA for astaxanthin biosynthesis from Haematococcus pluvialis, and astaxanthin synthesis in Escherichia coli . Plant Mol Biol, 29, 343-52. 

MISAWA N, SATOMI Y, KUNDON K, YOKOYAMA A, KAJIWARA S, SATO T, OHTANI T and MIKI W (1995) Strncture and functional analysis of a marine bacterial carotenoid biosynthetic gene clnster and astaxanthin biosynthetic pathway proposed at the gene eveV, J Bacteriol, 177, 6575-84. 

It has been established that carotenoid structure has a great influence in its antioxidant activity for example, canthaxanthin and astaxanthin show better antioxidant activities than 3-carotene or zeaxanthin. 3- 3 3-Carotene also showed prooxidant activity in oil-in-water emulsions evaluated by the formation of lipid hydroperoxides, hexanal, or 2-heptenal the activity was reverted with a- and y-tocopherol. Carotenoid antioxidant activity against radicals has been established. In order of decreasing activity, the results are lycopene > 3-cryptoxanthin > lutein = zeaxanthin > a-carotene > echineone > canthaxanthin = astaxanthin. ... 

It is assumed that in order to have vitamin A activity a molecule must have essentially one-half of its structure similar to that of (i-carotene with an added molecule of water at the end of the lateral polyene chain. Thus, P-carotene is a potent provitamin A to which 100% activity is assigned. An unsubstituted p ring with a Cii polyene chain is the minimum requirement for vitamin A activity. y-Car-otene, a-carotene, P-cryptoxanthin, a-cryptoxanthin, and P-carotene-5,6-epoxide aU have single unsubstimted rings. Recently it has been shown that astaxanthin can be converted to zeaxanthin in trout if the fish has sufficient vitamin A. Vitiated astaxanthin was converted to retinol in strips of duodenum or inverted sacks of trout intestines. Astaxanthin, canthaxanthin, and zeaxanthin can be converted to vitamin A and A2 in guppies. ... 

Landrum, J.T., Bone, R.A., and Herrero, C., Astaxanthin, cryptoxanthin, lutein, and zeaxanthin, in Phytochemicals in Nutrition and Health, CRC Press, Boca Raton, FL, 2002. 

Anon., 2002. Carotenoids What are carotenoids What do carotenoids do Astaxan-thin Biochemical Properties, Mera Pharmaceuticals, Inc. October 1, 2006. www.astaxanthin.org/carotenoids.htm. 

Zeaxanthin, lutein short-chain diesters and intermediates for canthaxanthin and astaxanthin synthesis... 

Recently, an enzymatic method was reported to recover the three main components of industrial shrimp waste (protein, chitin, and astaxanthin) using treatments with alcalase and pancreatin. The first enzyme was more efficient in increasing the recovery of protein from 57.5 to 64.6% and of astaxanthin from 4.7 to 5.7 mg/lOO g of dry waste. 

Lopez, M. et al.. Selective extraction of astaxanthin from crustaceans by use of supercritical carbon dioxide, Talanta, 64, 726, 2004. 

Section 5.3.2.3) combined with over-expression of IPPI resulted in enhanced astaxanthin accnmnlation to 1.4 mg/g dry cell weight (DCW). Further increases to 45 mg/g DCW were obtained by random mutagenesis of GGPPS, perhaps by altering enzyme response to substrate-level feedback inhibition. 

Higuera-Ciapara, L, Felix-Valenzuela, L., and Goycoolea, R, Astaxanthin a review of its chemistry and applications, Crit. Rev. Food Sci. Nutr. 46, 185, 2006. Voutilainen, S. et ah. Carotenoids and cardiovascular health. Am. J. Clin. Nutr. 83, 1265, 2006. 

Hussein, G. et ah, Astaxanthin, a carotenoid with potential in human health and nutrition, J. Nat. Prod. 69, 443, 2006. 

Mann, V. et al.. Metabolic engineering of astaxanthin production in tobacco flowers, Nat. Biotechnol. 18, 888, 2000. 

Wang, C.W., Oh, M.K., and Liao, J.C., Engineered isoprenoid pathway enhances astaxanthin production in Escherichia coli, Biotechnol. Bioeng. 62, 235, 1999. 

Verdoes, J.C., Misawa, N., and van Ooyen, A.J., Cloning and characterization of the astaxanthin biosynthetic gene encoding phytoene desaturase of XanthophyUomyces dendrorhous [letter], Biotechnol. Bioeng. 63, 750, 1999. 

Astaxanthin from Xanthophyllomyces dendrorhous Large-Scale... 

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